Editing Hypha (section)

==Growth==
Hyphae grow at their tips. During tip growth, cell walls are extended by the external assembly and [[polymerization]] of cell wall components, and the internal production of new cell membrane.<ref name="Gooday1995">{{Cite journal | last1 = Gooday | first1 = G. W. | title = The dynamics of hyphal growth | doi = 10.1016/S0953-7562(09)80634-5 | journal = Mycological Research | volume = 99 | issue = 4 | pages = 385–389 | year = 1995 }}</ref> The [[Spitzenkörper]] is an intracellular organelle associated with tip growth. It is composed of an aggregation of membrane-bound vesicles containing cell wall components. The Spitzenkörper is part of the [[endomembrane system]] of fungi, holding and releasing [[vesicle (biology)|vesicle]]s it receives from the [[Golgi apparatus]].  These vesicles travel to the cell membrane via the [[cytoskeleton]] and release their contents (including various cysteine-rich proteins including [[cerato-platanin]]s and [[hydrophobin]]s)<ref>{{cite journal |last1=Baccelli |first1=Ivan |last2=Comparini |first2=Cecilia |last3=Bettini |first3=Priscilla P. |last4=Martellini |first4=Federica |last5=Ruocco |first5=Michelina |last6=Pazzagli |first6=Luigia |last7=Bernardi |first7=Rodolfo |last8=Scala |first8=Aniello |title=The expression of the ''cerato-platanin'' gene is related to hyphal growth and chlamydospores formation in ''Ceratocystis platani'' |journal=FEMS Microbiology Letters |date=1 February 2012 |volume=327 |issue=2 |pages=155–163 |doi=10.1111/j.1574-6968.2011.02475.x |pmid=22136757 |doi-access=free |hdl=2158/645742 |hdl-access=free }}</ref><ref>{{cite journal |last1=Wösten |first1=Han A.B. |last2=van Wetter |first2=Marie-Anne |last3=Lugones |first3=Luis G. |last4=van der Mei |first4=Henny C. |last5=Busscher |first5=Henk J. |last6=Wessels |first6=Joseph G.H. |title=How a fungus escapes the water to grow into the air |journal=Current Biology |date=28 January 1999 |volume=9 |issue=2 |pages=85–88 |doi=10.1016/S0960-9822(99)80019-0 |pmid=10021365|s2cid=15134716 |doi-access=free |bibcode=1999CBio....9...85W }}</ref> outside the cell by the process of [[exocytosis]], where they can then be transported to where they are needed. Vesicle membranes contribute to growth of the cell membrane while their contents form new cell wall. The Spitzenkörper moves along the [[Apical (anatomy)#Elongated organisms with distinctive ends|apex]] of the hyphal strand and generates apical growth and branching; the apical growth rate of the hyphal strand parallels and is regulated by the movement of the Spitzenkörper.<ref>{{cite journal | last1 = Steinberg | first1 = G | year = 2007 | title = Hyphal growth: a tale of motors, lipids, and the Spitzenkörper | journal = Eukaryotic Cell | volume = 6 | issue = 3| pages = 351–360 | doi = 10.1128/ec.00381-06 | pmid = 17259546 | pmc = 1828937 }}</ref>

As a hypha extends, [[septum|septa]] may be formed behind the growing tip to partition each hypha into individual cells. Hyphae can branch through the bifurcation of a growing tip, or by the emergence of a new tip from an established hypha.